981 S Engine Failure at 43k miles
#31
#32
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Regular used oil analysis with expert review, along with periodic use of fuel system cleaners and more frequent oil changes are about all you can do. Part of these issues I believe are caused by ethanol fuels, but there is no way around this without regular fuel treatments or use of ethanol-free fuel.
We do make a 987.2 low temperature thermostat (used to be a Porsche Motorsports only item), but it will throw a pending fault for engine temp, however will not put the car into limp mode.
The 981 can be programmed with a PIWIS for hot climate operation where the electronic thermostat is re-programmed to run in an equivalent mode to having a low temperature thermostat.
We do make a 987.2 low temperature thermostat (used to be a Porsche Motorsports only item), but it will throw a pending fault for engine temp, however will not put the car into limp mode.
The 981 can be programmed with a PIWIS for hot climate operation where the electronic thermostat is re-programmed to run in an equivalent mode to having a low temperature thermostat.
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Voyager, do you know before/after how much the gt4 scoops improved cooling?
3.8L has held up well. I baby it in cold weather (garaged in winter in Ohio) and since I run the car at DEs and at drag strips a few times a year, I change oil before every track weekend and use Gibbs Driven DT40 and XP9 oils exclusively. The oil temperature is low on the car due to 3rd radiator, and I had BGB use reflective heat tape on the air filter housing, plenum, and intake manifolds, and have multiple coatings and wraps on the exhaust headers and mufflers. Hottest that oil has got (according to dash readout) is 238F and it goes to 200F seconds off the track. Last thing for cooling was adding GT4 side air scoops, which increase airflow through the engine compartment. I wanted to have fun with the car and have it last. All that cooling has the drawback of getting the oil up to temperature in the late fall as the car struggles to reach 170F when it is below 50F outside. I have had to start the car 30 minutes early to get oil up to temp before going on track at Mid-Ohio in October.
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Thanks Charles, this definitely helps. I wasn’t aware that fuel cleaners could reduce risk, are you suggesting Techron or another cleaner? Also would it still apply that the cleaner should only be used just before an oil change to make sure you don’t introduce any of the buildup into the oil?
Using Top Tier Fuels helps keep things clean and the testing on these fuels for moisture content, for example, is more strict, but I really do think that the ethanol fuels must be killing injectors due to reduced lubricity. When they reduced the sulfur content in fuels, that reduced lubricity and caused injector problems in diesels, but the "renewable" biomass added to diesels helped with this. Ethanol on the other hand reduces lubricity.
Driven, and several others, make ethanol fuel treatments. The Driven product is basically a Lubrizol product developed for the Brazilian market for corrosion protection and lubricity, as they run 100% ethanol in their cars down there. That's what we use and recommend.
If heavy treatment is needed (Driven product we use more as maintenance), we either pull the injectors and send them out (we're considering doing this at regular intervals) or use Lubromoly Jectron or a double dose of Seafoam in a pinch.
#35
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Regular used oil analysis with expert review, along with periodic use of fuel system cleaners and more frequent oil changes are about all you can do. Part of these issues I believe are caused by ethanol fuels, but there is no way around this without regular fuel treatments or use of ethanol-free fuel.
We do make a 987.2 low temperature thermostat (used to be a Porsche Motorsports only item), but it will throw a pending fault for engine temp, however will not put the car into limp mode.
The 981 can be programmed with a PIWIS for hot climate operation where the electronic thermostat is re-programmed to run in an equivalent mode to having a low temperature thermostat.
We do make a 987.2 low temperature thermostat (used to be a Porsche Motorsports only item), but it will throw a pending fault for engine temp, however will not put the car into limp mode.
The 981 can be programmed with a PIWIS for hot climate operation where the electronic thermostat is re-programmed to run in an equivalent mode to having a low temperature thermostat.
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flat6ix (05-16-2021)
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We've found several times scored bores and the offending cylinders had bad injectors that either didn't flow the right amount, leaked, or did not have proper spray patterns.
Using Top Tier Fuels helps keep things clean and the testing on these fuels for moisture content, for example, is more strict, but I really do think that the ethanol fuels must be killing injectors due to reduced lubricity. When they reduced the sulfur content in fuels, that reduced lubricity and caused injector problems in diesels, but the "renewable" biomass added to diesels helped with this. Ethanol on the other hand reduces lubricity.
Driven, and several others, make ethanol fuel treatments. The Driven product is basically a Lubrizol product developed for the Brazilian market for corrosion protection and lubricity, as they run 100% ethanol in their cars down there. That's what we use and recommend.
If heavy treatment is needed (Driven product we use more as maintenance), we either pull the injectors and send them out (we're considering doing this at regular intervals) or use Lubromoly Jectron or a double dose of Seafoam in a pinch.
Using Top Tier Fuels helps keep things clean and the testing on these fuels for moisture content, for example, is more strict, but I really do think that the ethanol fuels must be killing injectors due to reduced lubricity. When they reduced the sulfur content in fuels, that reduced lubricity and caused injector problems in diesels, but the "renewable" biomass added to diesels helped with this. Ethanol on the other hand reduces lubricity.
Driven, and several others, make ethanol fuel treatments. The Driven product is basically a Lubrizol product developed for the Brazilian market for corrosion protection and lubricity, as they run 100% ethanol in their cars down there. That's what we use and recommend.
If heavy treatment is needed (Driven product we use more as maintenance), we either pull the injectors and send them out (we're considering doing this at regular intervals) or use Lubromoly Jectron or a double dose of Seafoam in a pinch.
So SeaFoam and Lubromoly would be used before an oil change and Driven can be used anytime if I read your post correctly.
I have to admit the thought that ethanol is the potential culprit for the injector issues doesn’t entirely make sense to me. Most car manufacturers should have been fully aware of the addition of ethanol in our fuels by 2009 when these components were initially designed. You would think material specifications would include degradation resistance to ethanol. Even if it was overlooked I would think by the time the 981 was released they would have discovered the issue and made appropriate changes.
Any other theories out there such as a poor design and premature deterioration due to the high pressures involved with the injection system?
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Thank you Charles, again very helpful and appreciated.
So SeaFoam and Lubromoly would be used before an oil change and Driven can be used anytime if I read your post correctly.
I have to admit the thought that ethanol is the potential culprit for the injector issues doesn’t entirely make sense to me. Most car manufacturers should have been fully aware of the addition of ethanol in our fuels by 2009 when these components were initially designed. You would think material specifications would include degradation resistance to ethanol. Even if it was overlooked I would think by the time the 981 was released they would have discovered the issue and made appropriate changes.
Any other theories out there such as a poor design and premature deterioration due to the high pressures involved with the injection system?
I'm reading through several SAE whitepapers now.
For the record, there is no current ASTM test for gasoline lubricity and from what I've read thus far, the consumer is the guinea pig.
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Interesting stuff, definitely. One dilemma I have is that while I do have access to ethanol-free 92 (RON+MON)/2 gas, the station is not very convenient, being about 10 miles away. So I end up using the usual Shell premium gas in my '13 981S. The Shell product obviously has a good Top Tier additive package, but is also E10. Conversely, I have no idea where the ethanol-free gas comes from, or indeed if it has any additives at all.
The car runs well on both, maybe a tiny bit better on the ethanol-free gas, depending on my perceptions that day and (possibly) whether the Shell is a summer or winter formulation. I haven't noticed any difference at all in fuel economy.
So the question is, if my goal is engine longevity, should I stick with Shell or drive a few miles farther for the "good stuff" that might or might not be all that "good?"
Compounding my confusion is the conventional wisdom that additives are not meaningful at all for DI engines, since the fuel never comes anywhere near the valve seats. That would be an argument in favor of the ethanol-free product... but is it a valid one?
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We have Used OEM Porsche 3.8L Engine for a GT4 with 5,000 track miles on it. Comes as a complete engine ready to install in any GT4 CS / MR. If you wanted to use this in a street car, the wiring harness and flywheel would need to be swapped.
No core needed $18k.
No core needed $18k.
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$18K for 5,000 track miles?! Pull the other one.
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Eh, that's probably only 20-30 track days. Some folks do that in a single year on a stock 9A1. I know at least one member here said he had 70-80 days on his. I do 120-200 miles on track per day usually.
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The motor that im offering for sale came out of a GT4 CS with 5,000 on the odometer. Since these aren't street legal vehicles, it has only seen the track. In reality its not much mileage compared to whats out there currently running in Clubsports worldwide.
Note:
We have customers with GT4 street cars that log over 8,000 track miles per year.
Note:
We have customers with GT4 street cars that log over 8,000 track miles per year.
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Since this motor came out of a clubsport, it only saw the track and 5,000 isn't much at all in regards to what claims you'll get out of the motor if maintained properly. Each time our vehicles come off track for the weekend, they get a full fluid service in order to ensure the longevity of the motor.